12-year span since Foresthill Bridge got full inspection

In the pantheon of spectacular California bridges, the stiletto-thin Foresthill span outside Auburn stands out. At 730 feet, its canyon-spanning roadway is the highest in the state.

Since the catastrophic Minneapolis bridge collapse in August, the foothill span is iconic in a worrisome new way.

Foresthill Bridge, which shares the same architecture as the Minneapolis bridge, has not undergone a full, up-close inspection of all girders since 1995, according to inspection records.

That falls short of federal requirements that all key girders be checked at arms distance every two years.

State officials say they have conducted close inspections of most of the bridge's important girders every two years and insist the bridge is safe.

But they acknowledge that some hard-to-reach sections of the deep-trussed bridge have not been inspected at close range in many years.

State bridge inspections chief Barton Newton said he believes the agency is complying with the intent of federal regulations.

Nevertheless, he said he asked his staff this week to pull together a list of other "hard-to-reach" bridges so that those inspection records could be reviewed. He estimated there may be several dozen such bridges around the state.

"We realize we have access problems on some bridges," Newton said. "That is a challenge for us."

Federal regulations require certain "fracture critical" bridges, such as Foresthill, to have arm's-length inspections of all critical girders every two years.

The "fracture critical" designation is given to bridges that do not have backup girders, leaving them at greater risk of collapse should a girder fail.

Federal Highway Administration officials said they have been briefed by the State Transportation Department and believe California is making a good-faith effort to comply with federal rules.

"It is not as if they are ignoring the regulations, or picking and choosing for convenience," highway administration spokesman Ian Grossman said. "They are being reasonable, and they are taking the right steps to move forward."

In the case of the Foresthill Bridge, inspection reports indicate the mechanical arms on the state's two half-million-dollar snooper trucks aren't long enough to maneuver inspectors in a mechanical bucket to some lower girders.

Caltrans officials say they have, however, viewed those girders from a distance and did not feel there was a need to incur the costs and safety risks of sending inspectors climbing onto the girders for closer looks.

Newton said partial inspections – including one this August – leave him confident the 35-year-old bridge over the north fork of the American River is solid.

"We have no concerns about safety, no urgent needs," Newton said.

A Bee review of recent inspection reports indicates officials have found no major problems on the bridge.

But, in his August report, an inspector at Foresthill noted that recent inspections have not gotten to all girders and recommended "a complete fracture critical inspection for this structure be scheduled and performed as soon as possible."

Newton said he plans a girder-by-girder look at the bridge during its regularly scheduled review next August.

The decision, he said, was spurred in part by the post-Minneapolis climate of higher scrutiny.

Foresthill is one of 69 bridges in California with a steel deck truss construction similar to the Minneapolis bridge. It is the only sizable bridge in the Sacramento area with that kind of construction.

It also is one of 1,000 "fracture critical" bridges in the state. Most of those bridges, Newton said, have easily accessible girders and are getting full reviews.

Caltrans' Newton said his department is buying two new snooper trucks with a longer reach, which should allow inspectors to get to the deepest girders in the Foresthill Bridge without having to climb.

If that doesn't work, he said he would pay to have ropes and scaffolding set up under the bridge deck so inspectors could more safely reach lower girders on foot.

Some officials say increased safety requirements have hindered inspections by making climbing more costly and time-consuming.

"We used to just climb out there and walk on the trusses like ironworkers," inspector Paul Hartbower said. "We didn't think twice about it."

Under new rules, he said, it "was taking so much time to gear up and tie down and tie off, you weren't getting anything done."

Caltrans stopped certifying inspectors as climbers several years ago.

Newton defended Caltrans' inspection program, saying inspectors can get a good sense of most bridges' stability by getting close to some girders and checking others from a greater distance for warping and other stress signs. If that basic level of review shows problems, inspectors look more deeply, Newton said.

That allows the agency to focus more effort on troublesome bridges, Newton said. "We don't manage our bridges on a one-size-fits-all basis."

Cornell University professor Anthony Ingraffea, head of that school's steel fracture research group, said that approach is similar to what is done in the aviation industry, where older planes with more problems get more frequent and closer inspections.

In Placer County, public works official Kevin Ordway says he respects Caltrans' expertise. But, he said, even though the bridge is young, it carried heavy logging trucks for years and needs maintenance work and a seismic retrofit.

"It'd be nice if they can have a climb team" check the bridge, Ordway said. "I would feel the bridge is more thoroughly inspected."

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